
Muscle-Wasting Disease in Elephant Seal Pups
- Pathology
Abstract
A field study addressing causes of mortality in freshly dead northern elephant seals (Mirounga angustirostris, Gill, 1866) was conducted on San Miguel Island, California, in February 2015. Necropsies were performed on 18 pups ranging in age from stillbirths to approximately 7 to 8 weeks. The primary gross diagnoses in these pups included trauma, myopathy, starvation/emaciation, infections, congenital anomalies, and perinatal mortality. However, 6 (33%) had a previously unrecognized myopathy characterized by multiple white streaks that were most obvious within the inner layer of the abdominal wall and the small innermost ventral intercostal muscles. Following histological examination, 2 more pups from San Miguel Island and 6 pups from The Marine Mammal Center (Sausalito, California) were found to have similar lesions. Histologically, the lesions within the skeletal muscles were characterized by a multifocal polyphasic, mild to severe, acute to subacute necrotizing myopathy with mineralization. Acute necrosis and degeneration characterized by pyknotic nuclei, eosinophilic cytoplasm and cytoplasmic vacuolization were found in smooth muscle myocytes within the urinary bladder and digestive system. Degeneration of myocytes was present in the tunica media of a few small- to medium-sized vessels and was characterized by a vacuolar degeneration and occasionally necrosis. This condition has been termed multifocal necrotizing myopathy. A cause of this myopathy was not identified.
Spraker, T.R., Kuzmina, T.A., Lyons, E.T., DeLong, R.L., Simeone, C. and Veeramachaneni, D.R., 2019. Multifocal Necrotizing Myopathy in Northern Elephant Seal (Mirounga angustirostris) Pups, San Miguel Island, California. Veterinary pathology, 56 (1, January), pp.143-151.
Related Publications
{"image":"\/Animals\/Wild\/Bottlenose dolphin\/bottlenose-dolphins-leaping-shutterstock.jpg","alt":"dolphins leaping out of the water","title":"Fresh Water Skin Disease in Dolphins","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/fresh-water-skin-disease-in-dolphins","label":"Research Paper"}

{"image":"\/Animals\/Wild\/Sea otter\/cropped-images\/sea-otter-grooming-head-shutterstock-22-86-3617-2826-1616709449.jpg","alt":"sea otter grooming","title":"Parasitic Skin Disease in Threatened Southern Sea Otters","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/parasitic-skin-disease-in-threatened-southern-sea-otters","label":"Research Paper"}

{"image":"\/Animals\/Wild\/Other species\/cropped-images\/galapagos-sea-lion-shutterstock-954-376-2988-2334-1617750524.jpg","alt":"Galapagos sea lion","title":"Mycoplasmas in Galapagos Sea Lions and Their Association with Other Respiratory Pathogens","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/occurrence-of-mycoplasmas-in-galapagos-sea-lions","label":"Research Paper"}

Mycoplasmas in Galapagos Sea Lions and Their Association with Other Respiratory Pathogens
Read More{"image":"\/Animals\/Wild\/Other species\/cropped-images\/stejnegers-beaked-whale-photo-c-marc-webber-0-0-949-742-1618440217.jpg","alt":"Stejneger's beaked whales","title":"Stejneger's Beaked Whale Strandings in Alaska, 1995\u20132020","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/stejnegers-beaked-whale-strandings-in-alaska-1995-2020","label":"Research Paper"}

Related News
{"image":"\/Animals\/Wild\/Humpback whale\/cropped-images\/whale-tail-with-bridge-and-ships-shutterstock-3-7-4898-3826-1663722256.jpg","alt":"whale tails visible above water under the Golden Gate Bridge with shipping traffic in the distance","title":"Whale Safe \u2013 an AI-enabled System to Prevent Ship Collisions with Whales \u2013 to Launch off the San Francisco Coastline","link_url":"https:\/\/www.marinemammalcenter.org\/news\/whale-safe-to-launch-off-the-san-francisco-coastline","label":"Press Release","date":"2022-09-21 04:00:00"}

Whale Safe – an AI-enabled System to Prevent Ship Collisions with Whales – to Launch off the San Francisco Coastline
September 21, 2022
Read More{"image":"\/Animals\/Wild\/Humpback whale\/cropped-images\/two-whales-under-golden-gate-bridge-shutterstock-646-1-3946-3083-1663782644.jpg","alt":"two whales surfacing below the Golden Gate Bridge","title":"New York Times: New System Aims to Save Whales Near San Francisco From Ship Collisions","link_url":"https:\/\/www.marinemammalcenter.org\/news\/new-york-times-new-system-aims-to-save-whales-near-san-francisco-from-ship-collisions","label":"In the News","date":"2022-09-21 02:00:00"}

New York Times: New System Aims to Save Whales Near San Francisco From Ship Collisions
September 21, 2022
Read More{"image":"\/Animals\/Wild\/Humpback whale\/cropped-images\/fran-humpback-whale-photo-c-doug-croft-blue-ocean-whale-watch-473-0-2161-1688-1661961931.jpg","alt":"Fran the humpback whale leaping out of the water","title":"Humpback Whale Killed by Suspected Ship Strike Was One of the Most Well-Known Whales in California","link_url":"https:\/\/www.marinemammalcenter.org\/news\/humpback-whale-killed-by-suspected-ship-strike-was-one-of-the-most-well-known-whales-in-california","label":"Press Release","date":"2022-08-31 02:00:00"}

Humpback Whale Killed by Suspected Ship Strike Was One of the Most Well-Known Whales in California
August 31, 2022
Read More{"image":"\/Animals\/Wild\/Humpback whale\/cropped-images\/humpback-whale-breach-photo-c-bill-hunnewell-422-0-3324-2597-1658185516.jpg","alt":"humpback whale breaching","title":"Forbes: Huge Humpback Whale\u2014And California Celebrity\u2014Killed In Ship Strike Amid Concern Over Collisions","link_url":"https:\/\/www.marinemammalcenter.org\/news\/forbes-huge-humpback-whaleand-california-celebritykilled-in-ship-strike-amid-concern-over-collisions","label":"In the News","date":"2022-08-31 02:00:00"}

Forbes: Huge Humpback Whale—And California Celebrity—Killed In Ship Strike Amid Concern Over Collisions
August 31, 2022
Read More